The function, application scope and composition characteristics of steering knuckle are introduced.

News source：web Release time：2022-07-14

I. introduction to steering section:

The steering knuckle is one of the main parts on the steering bridge of an automobile, which can make the automobile run stably and transmit the driving direction sensitively. Under the driving condition of a car, it is subject to variable impact load, so it is required to have high strength. The steering section is connected to the body through three bushings and two bolts, and to the braking system through the brake mounting hole of the flange plate. When a vehicle is driving at high speed, the vibration of the road surface to the steering knuckle through the tire is the main factor to be considered in our analysis. In the calculation, the existing vehicle model is used to apply the gravity acceleration of 4G to the whole vehicle, and the support and reaction forces of the three center points of the steering knuckle bush and the two center points of the bolt mounting hole are calculated as the applied load, and the 123456 degrees of freedom of all the joints on the end face of the braking system connected to the flange plate are restrained.

Ii. Components of steering knuckles:

The steering shaft consists of a steering knuckle and a transmission shaft, and is sometimes supported in the middle. It is mainly used to transfer torque and rotary motion between two shafts whose relative positions are constantly changing during the working process. Steering drive shaft is widely used in automobiles. In a car driven by the front rear wheel of the engine or the whole wheel, the relative position of the output shaft of the transmission or sub-actuator and the input shaft of the drive bridge is often changed due to the deformation of the elastic suspension. In the steering drive axle, the Angle between the inner and outer half shafts changes with the need of driving. When the rear drive bridge is a separate suspension, the steering shaft must also be used.

The steering knuckle can be divided into rigid steering knuckle and flexible steering knuckle. Rigid steering knuckles transfer power by hinge joints of parts, which can be divided into non-uniform steering knuckles (such as cross-axis ones), quasi-uniform steering knuckles (such as couplets, convex blocks, tripin shafts, etc.) and constant speed steering knuckles (such as ball forks and ball cages). The flexible steering knuckle is powered by a flexible part and is used for cushioning and damping.

Unisokinetic steering knuckle refers to a steering knuckle with an average angular velocity ratio of 1, when the Angle between two shafts connected by the steering knuckle is greater than zero, the movement between the output axis and the input axis is transmitted by the instantaneous angular velocity ratio of change. Quasi-isokinetic steering knuckle refers to the steering knuckle with the instantaneous angular velocity ratio equal to 1 when working at the design Angle, and the instantaneous angular velocity ratio approximately equal to 1 when working at other angles. The output axis and the input axis transfer the steering knuckle of motion at an instantaneous angular velocity equal to 1, which is called the isokinetic steering knuckle.

Iii. Composition characteristics of steering knuckles:

The shape of universal joint is quite complex, and the structural features of four types of parts, such as shaft, sleeve, disc ring and fork frame, are concentrated. The structural shape of the supporting shaft neck is a stepped shaft, and its structural characteristics are composed of the outer cylinder face, cone face and thread face of the same axis, as well as the shaft shoulder, transition Angle and end face perpendicular to the axis line. The flange plate comprises a flange face, a uniform bolted through-hole and a screw-hole in the steering limit; The fork frame is composed of the upper, lower ear and flange of the knuckle.